以动态方式插入数组的大小并将旧值保留在数组中

Is that possible that I can increase the size of Array dynamically and keep the old value in the Array. We don't know the size of array as user is keep inserting the value and we have to change the array length after every input. So I will appreciate if somebody has better alternative then what I am trying to achieve.Is that possible that I can increase the size o